Kiyoshi Kobayashi was a Japanese actor, voice actor, and narrator from Tokyo, born on January 11, 1933. He was a graduate of the arts department of Nihon University. Before entering the world of voice acting, he worked as a stage actor with the theater company Izumi-za. His career in voice acting began with dubbing work for foreign films and television series, a field where his proficiency in English translation was a significant asset. In 1960, he was a founding member of the Tokyo Actor's Consumer's Cooperative Society, commonly known as Haikyo, the talent agency he was affiliated with for the rest of his life. Kobayashi passed away on July 30, 2022, from pneumonia at the age of 89.

Kobayashi's career was distinguished by his deep, distinctive baritone voice, which made him a sought-after talent from the early days of the voice acting industry in Japan. He was particularly renowned for his work in dubbing, serving as the official Japanese voice for Western actors such as James Coburn and Lee Marvin for many years.

However, his most iconic and enduring role was as Daisuke Jigen, the sharp-shooting partner of Arsène Lupin III, in the long-running Lupin the Third series. He first voiced the character in the 1969 pilot film and continued for over 50 years, holding the record for the longest time a single voice actor has portrayed the same character in a Japanese animated series. The connection between Kobayashi and the character was profound; Jigen was modeled after actor James Coburn, for whom Kobayashi was the regular dub-over voice, making him the only choice for the role from the very beginning. Kobayashi himself described Jigen as the culmination of his work and synonymous with himself. He continued to voice the character until his retirement in 2021, with his final performance being in Episode 0 of Lupin the Third Part 6.

Beyond Lupin III, Kobayashi had an extensive and varied filmography across multiple decades. Some of his other notable anime roles included Bem in Humanoid Monster Bem, Watari in Death Note, Muhammad Avdol in JoJo's Bizarre Adventure, Crystal Bowie in Space Adventure Cobra, and Aiguille Delaz in Mobile Suit Gundam 0083: Stardust Memory. He also frequently served as a narrator for numerous anime series, such as The King of Braves GaoGaiGar, and for various television programs.

In recognition of his long-standing contributions and achievements in the voice acting industry, Kiyoshi Kobayashi was honored with the Merit Award at the 11th Seiyu Awards in 2017. His legacy is defined by his iconic portrayal of Daisuke Jigen and a body of work that spans the history of Japanese animation and voice-over.